Warp Perspective OpenCV Python With Source Code
This Python Project With Source Code will show you how to apply warping transformations to obtain a “birds-eye-view” of given cards image. From there, we will be able to crop out the selected card.
What is OpenCV?
OpenCV is short for Open Source Computer Vision. Intuitively by the name, it is an open-source Computer Vision and Machine Learning library.
This library is capable of processing real-time image and video while also boasting analytical capabilities. It supports the Deep Learning frameworks.
In this Python OpenCV Project also includes a downloadable Python Project With Source Code for free, just find the downloadable source code below and click to start downloading.
By the way if you are new to python programming and you don’t know what would be the the Python IDE to use, I have here a list of Best Python IDE for Windows, Linux, Mac OS that will suit for you.
I also have here How to Download and Install Latest Version of Python on Windows.
To start executing Warp Perspective OpenCV Python With Source Code, make sure that you have installed Python 3.9 and PyCharm in your computer.
Warp Perspective OpenCV Python With Source Code: Steps on how to run the project
Time needed: 5 minutes
These are the steps on how to run Warp Perspective OpenCV Python With Source Code
- Step 1: Download the given source code below.
First, download the given source code below and unzip the source code.

- Step 2: Import the project to your PyCharm IDE.
Next, import the source code you’ve download to your PyCharm IDE.

- Step 3: Run the project.
last, run the project with the command “py main.py”

Installed Libraries
import cv2 import numpy as np
Complete Source Code
################### Simple Detect #############
# import cv2
# def mousePoints(event,x,y,flags,params):
# if event == cv2.EVENT_LBUTTONDOWN:
# print(x,y)
#
# img = cv2.imread('Resources/cards.jpg')
# cv2.imshow("Original Image ", img)
# cv2.setMouseCallback("Original Image ", mousePoints)
# cv2.waitKey(0)
######### WARP PRESPECTIVE IMPLEMANTAION WITH MOUSE CLICKS ##################
import cv2
import numpy as np
circles = np.zeros((4,2),np.int)
counter = 0
def mousePoints(event,x,y,flags,params):
global counter
if event == cv2.EVENT_LBUTTONDOWN:
circles[counter] = x,y
counter = counter + 1
print(circles)
img = cv2.imread('card.jpg')
while True:
if counter == 4:
width, height = 250,350
pts1 = np.float32([circles[0],circles[1],circles[2],circles[3]])
pts2 = np.float32([[0,0],[width,0],[0,height],[width,height]])
matrix = cv2.getPerspectiveTransform(pts1,pts2)
imgOutput = cv2.warpPerspective(img,matrix,(width,height))
cv2.imshow("Output Image ", imgOutput)
for x in range (0,4):
cv2.circle(img,(circles[x][0],circles[x][1]),3,(0,255,0),cv2.FILLED)
cv2.imshow("Original Image ", img)
cv2.setMouseCallback("Original Image ", mousePoints)
cv2.waitKey(1)Output:

Download Source Code below
Anyway, if you want to level up your programming knowledge, especially Python OpenCV, try this new article I’ve made for you Best OpenCV Projects With Source Code For Beginners.
Summary
In this Python Project With Source Code we applied perspective and warping transformations using Python and OpenCV.
We utilized the cv2.getPerspectiveTransform and cv2.warpPerspective functions to accomplish these transformations.
We then reviewed a perspective transform OpenCV example.
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Inquiries
If you have any questions or suggestions about Warp Perspective OpenCV Python With Source Code, please feel free to leave a comment below.
Technology stack and requirements
To run this Python project on your development machine, you need:
- Python 3.10 or higher. Download from python.org or install via Anaconda if you prefer bundled packages.
- pip package manager. Comes with Python. Used to install project dependencies from requirements.txt.
- Virtual environment. Use venv or conda to isolate project dependencies from your global Python install.
- VS Code or PyCharm. Free code editors with Python syntax highlighting, IntelliSense, and debugging.
- Git. For version control and cloning source code repositories.
Installing the source code
- Download or clone the repository. Get the ZIP archive from the download link on this page and extract it.
- Create a virtual environment. Open a terminal in the project folder and run: python -m venv venv, then activate it (venv\Scripts\activate on Windows or source venv/bin/activate on Mac/Linux).
- Install dependencies. Run pip install -r requirements.txt to install all libraries the project needs.
- Configure environment variables. If the project uses API keys (OpenAI, Anthropic, database), create a .env file and set the required keys.
- Run the project. Follow the run command in the README (usually python main.py or streamlit run app.py).
Using this project for your BSIT capstone
- Chapter 1 (Introduction). Discuss the real-world problem this system solves. Cite Philippine or international use cases where the manual process could be automated.
- Chapter 2 (RRL). Compare your project against 5-10 similar published works. Cite ACM, IEEE, or arXiv papers for academic-standard sources.
- Chapter 3 (Methodology). Document the model architecture, training data, hyperparameters, and evaluation metrics used.
- Chapter 4 (Results). Report accuracy, precision, recall, F1-score, and confusion matrix. Screenshot the running app on real inputs.
- Chapter 5 (Conclusion). Identify features for Version 2: better model, larger dataset, mobile deployment, or REST API.
Modules typical of Warp Perspective OpenCV Python
- Image dataset preparation. Train/val/test split, augmentation (rotation, flip, brightness).
- Model architecture. Pre-trained CNN (ResNet, EfficientNet) fine-tuned on your dataset.
- Training loop. PyTorch or TensorFlow/Keras training with early stopping and checkpoints.
- Evaluation. Confusion matrix, precision, recall, and per-class F1 scores.
- Inference API. FastAPI endpoint accepting image uploads and returning predictions.
- Web or mobile demo. Streamlit or React front-end for user interaction.
Common enhancements for capstone review
- Grad-CAM visualization. Show which pixels the model focused on when making a prediction.
- Data augmentation. Increase training data variety with imgaug or Albumentations library.
- Transfer learning benchmark. Compare training-from-scratch vs fine-tuning pre-trained models.
- Model quantization. Convert to TensorFlow Lite for mobile deployment.
Official documentation
Frequently Asked Questions
How does OpenCV warp perspective work?
cv2.getPerspectiveTransform(src_pts, dst_pts) computes a 3×3 transformation matrix from 4 source points (corners of a quadrilateral in your image) to 4 destination points (corners of the desired rectangle). Then cv2.warpPerspective applies that matrix to dewarp the region. Common use: scan a tilted document and produce a flat top-down view.
What OpenCV version do I need to run this project?
Use OpenCV 4.5 or newer. Install with pip install opencv-python (the standard build for desktop projects). Some projects also need opencv-contrib-python which adds extra modules (SIFT, SURF, advanced trackers). The pip install command auto-downloads pre-built wheels so no compilation is needed on Windows, Mac, or Linux.
How do I install OpenCV and the dependencies for this project?
Open a terminal, then: pip install opencv-python numpy. Most projects also need one of these: mediapipe (for face / hand / pose detection), pyzbar (for barcode and QR), pytesseract (for OCR), Pillow (for image manipulation), pyautogui (for screen capture). Pin Python version to 3.10, 3.11, or 3.12 for maximum library compatibility.
Can I use this OpenCV project for a BSIT or CSE capstone?
Yes, but extend it. A single OpenCV demo (face detection alone, lane detection alone) is too narrow for full capstone scope. Combine it with a real domain (attendance system using face recognition, traffic monitoring system using lane detection, fitness coach app using pose detection), add a database to log results, build a simple Tkinter or Streamlit UI, and document the whole pipeline in Chapter 3.
Why am I getting AttributeError or ImportError when running this code?
Three most common causes: (1) You installed opencv-python but the code needs opencv-contrib-python (extra modules like xfeatures2d). Reinstall with pip install opencv-contrib-python. (2) You are on Python 3.13 but some wheels (mediapipe) lag behind, downgrade to Python 3.11 or 3.12. (3) NumPy version mismatch, pin numpy to a version your other libraries support.
Where do I find more OpenCV and Machine Learning project ideas?
Browse our Machine Learning Projects hub for 23+ OpenCV demos with source code. For capstone-scale AI ideas (RAG, NLP, recommendation systems), see 100+ AI Capstone Project Ideas. For broader Python project ideas, our Python Projects library has 250+ working capstones.



